Refrigerating apparatus



Nov. 27, 1945. N. ERLAND AF KLEEN REFRIGERATING APPARATUS Filed 001;. s, 1941 Sheets-Sheet 1 mafia R m Z T a 3 WI ,4 WWW a M 1 w mu. WY m m:

N. ERLAND AF KLEEN Nov. 27, 1945.

I A BEFR IGERATING APPARATUS 5 Sheets-Sheet 3 Filed Oct. 3, 1941 INVENTOR.

BY W

M 4 TTO/P/VEY Nov. 27, 1 945;- N. ERLAND AF KLEEN REFRIGERATING APPARATUS Filed on. 3, 1941 v 5 Sheets-$11991: 4

Patented Nov. 27, 1945 REFRIGERATING APPARATUS Nils Erland af Kleen, Stockholm, Sweden, assign or to Kleen Refrigerator, Inc., Hoboken, N. J.,' a corporation of Delaware Application October 3, 1941, Serial No. 413,441

16 Claims.

This invention relates to new and useful improvements in refrigerating apparatus and more particularly to an evaporator or cooling unit for household refrigerator cabinets.

It is desirable and advantageous as disclosed in my earlier Patent No. 2,319,806 to employ in of the cabinet in which the said part is separated from the ice freezing chamber in a heat'conducting respect sothat by operating each of said evaporator or cooling parts on alternate cooling and inactive periods, the part employed for cooling circulating air. in the cabinet will become coated with frost during its cooling period and be defrosted during its inactive period. By employing a pair of such parts for ice: freezing and a separate pair of such parts for cooling circulating air and operating the evaporator or cooling parts of each of said pairs in out of phase relation to one another so that when one of said evaporator or cooling parts of each of said pairs is inactive the other one of said parts of each of said pairs is active to produce a cooling effect, substantially continuous refrigeration will be provided for ice freezing and for cabinet cooling and a relatively high humidity will be maintained in' the storage space of the cabinet-by automatic defrosting of the cabinet cooling parts.

However, where the freezing chamber is not thermally insulated from the food storage compartment and each side of the freezing chamber presents a relatively large surface to circulating air in said compartment, the side of the freezing chamber that is not cooled during the inactive period of the evaporator part thermally bonded thereto will be heated up by the circulating air passing in heat exchange relation thereto inasmuch as the average temperature maintained in the food storage compartment is usually higher than that maintained in the freezing chamber. Moreover, Where, as shown in the above-mentioned patent, one of the evaporator parts of the pair employed for aircooling and arranged on one side of the freezing chamber is also inactive at the same time as one of the evaporator parts chamber to a greater extent than would otherwise be the case if the air were comparatively cold. Consequently, the efficiency of the cooling unit for ice freezing will be-materially impaired. The present invention is an improvement on a cooling unit of the type hereinbefore mentioned and has for its primary object to reduce to a minimum-the extent of heating up of the sides of the freezing chamber by the circulating air in the food storage compartment during the inactive periods of the respective evaporator parts thermally bonded to said freezing chamber.

According to the present invention, each side of the freezing chamber is provided witha pair of the pair employed for ice freezing and arranged 0n the same side of the freezing chamber, the air passing in heat exchange relation with the said side of the freezing chamber will be comparatively warm and will heat up the freezing of evaporator. parts in which one of the evaporator parts of said pair is in thermal contact with the freezing chamber to cool the latter and the other one of the evaporator parts of said pair is out of thermal contact with said freezing chamher to cool the air passing in heat exchange relation with the said side of the'freezing chamber during the inactive periods of the first-named evaporator part. I

Another object of the present invention is to provide in a refrigerator cabinet a new and improved evaporator or cooling unit comprising a plurality of evaporator or cooling parts having alternate cooling and inactive periods and arranged in pairs including one pair for ice freezing or the like in which the evaporator parts are thermally bonded to a freezing chamber and are disposed on opposite sides respectively of the chamber and another pair for cooling circulating air passing in heat exchange relation with the said sides of the freezing chamber during the inactive periods of the respective evaporator parts of the first-named pair and in which the evaporator parts of the said second-named pair are arranged out of thermal contact with respect to one another andto the freezing chamber so as to be automatically defrosted during their respective inactive periods. The above and other objects and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which similar reference characters have been used to indicate like parts throughout the several views and in which Fig. 1 is a diagrammatic view of a household refrigerator embodying the present invention;

.Fig, 2 is an isometric view of the evaporating v systems forming the evaporator unit of Fig. 1;

Fig. 3 is a view similar to Fig. 1 of a modified form of-evaporator'unit;

Fig. 4 is a detail view in front elevation of another form of evaporator unit;

Fig. 5 is a view similar to Fig. 3 of another modification;

Fig. 6 is an isometric view of the cooling coil of one evaporating system forming one side, or one-half of an evaporator unit in accordance with the present invention;

the separate coils of the evaporator unit, and

Fig. 9 is a detail view of an evaporator unit formed by two separate closed indirect cooling circuits.

Referring to the drawings, and more particularly to Fig. l, the refrigerating apparatus diagrammatically illustrated is of the intermittent absorption type and consists of a pair of units operating in out of phase relation to each other. For brevity, only the parts of the unit shown in the left hand side of the figure will be described by reference characters, the corresponding parts for the unit shown in the right hand side being distinguished by the letter a.

Each unit comprises a boiler-absorber or generator-absorber I containing strontium chloride or other suitable absorbent ll capable of absorbing ammonia or other refrigerant fluid employed, a condenser M provided with heat dissipating fins common to both units and arranged to be cooled by air, a receiving vessel l6 embedded in the thermal insulation of the refrigerator cabinet l1, and a pair of evaporator or coolingparts l9 and 20 shown in the form of vertical coils located within the thermally insulated storage space ll! of the cabinet.

The absorbent chamber of the boiler-absorber i0 is connected by a conduit iii to the condenser l4 and the latter in turn is connected by a conduit l to the vessel IS. The evaporator coils l9 and 20 are connected to the vessel IS in a parallel arrangement and each has an inlet connection for refrigerant liquid with the bottom of the vessel and also has a return or outlet connection for refrigerant vapor with the upper portion ofv said vessel above the normal level of liquid in the latter as best seen from Fig. 2.

The evaporator coil is is welded or otherwise thermally bonded to the heat conducting shell of an ice freezing compartment 2| so as to provide a comparatively low temperature in the latter. On the other hand, the evaporator coil 20 is arranged out of thermal contact with the freezing vapors liberated under influence of the heat supplied pass from the absorbent chamber by way of conduit l3 to the condenser l4 where they are liquefied by the cooling action of the cooling air and the refrigerant liquid is delivered by conduit l5 to the vessel l6 and evaporator coils l9 and 20. Following this period of operation of the unit, heating of the boiler-absorber I0 is interrupted and the latter is cooled during the absorbing period of the unit in any suitable manner known in the art. During this cooling or absorbing period, the refrigerant liquid evaporates in the evaporator coil 19 in heat exchange relation with the ice freezing compartment 2| to cool the latter and also evaporates in the evaporator coil 20 in heat exchange relation with the air in the storage space ill of the cabinet I! and the refrigerant vapor is absorbed by the absorbent ll. Upon completion of the absorbing period, heat is again supplied to the boiler-absorber by the heater I2 to repeat the cycle of operation just described, the change-over from generating to absorbing and vice versa being controlled by any suitable means known in the art.

In the form of the invention illustrated in Figs. 1 and 2, the evaporator or cooling part I8 compartment 2| and is preferably provided with a heat transferring plate 22 having ribs 23 to.

present a comparatively large cooling surface for the air in the storage space l8.

Thus, each unit has a plurality of evaporator or cooling parts including one arranged in direct thermal transfer relationship with respect to the ice freezing compartment 2| and another arranged in indirect thermal transfer relationship with respect to said compartment.

The boiler-absorber I0 is heated by a gas burner or other suitable heating means I! to liberate the refrigerant from the absorbent ll during the generating period of the unit. The refrig rant of one unit and the evaporator or cooling part 19a of the other unit are arranged respectively onthe left and right sides of the ice freezing compartment 2| and in good thermal contact therewith. On the other hand, the evaporator or cooling part 20 of the first-named unit and the evaporator or cooling part 20a of the secondnamed unit are arranged respectively on the right and left sides of the ice freezing compartment II and spaced outwardly therefrom and from the adjacent ones of said first-named evaporator parts so as to provide a pair of channels 24 and a along the left and right sides, respectively, of the ice freezing compartment for the air circulating in the storage space I 8 of the cabinet l'i.

Thus each of the air channels 24 and 24a is formed between a separate pair of cooling parts or cooling sections, in which one of the cooling parts of each pair forms one of the evaporator parts of one unit and is arranged in thermal contact with the ice freezing compartment 2| and the other one of the cooling parts or cooling sections of each pair forms one of the evaporator parts of the other unit and is arranged out .of thermal contact with said compartment.

In this manner, during the absorbing period of the left unit, the ice freezing compartment 2| will be cooled by the evaporator part [9 in thermal contact therewith along the left side thereof and the air passing through the channel 24 along the said side of the compartment will also be cooled by said evaporator part I9 while the air passing through the'channel 24a along the right side of the compartment 2! will be cooled by the evaporator part 20 arranged out of thermal contact with said compartment. In like manner, during the absorbing period of the right unit, the ice freezing compartment 2 I will be cooled by the evaporator part I911 in thermal contact therewith along the right side thereof and the air passing through the channel 24a along the said side of the compartment will also be cooled by said evaporator part I90 while the air passing through the channel fl along the right side of the compartment 2| will be cooled by the evaporator part 20a arranged out of thermal contact with said compartment.

, Consequently, with the units operating in out of phase relation to one another, not only will .named pair of evaporating systems.

' is provided along the heating up influence on the ice freezing compartment of the air in the food storage space I8.

Moreover, inasmuch as the evaporator part 20 of one unit and the evaporator part 20a of the other unit are arranged out of thermal contact with the ice freezing compartment 2| and also out of thermal contact with one another, each of said evaporator parts will assume a comparatively low temperature and become coated with frost during its active period and will assume a comparatively high temperature and be defrosted during its inactive period so that a relatively high humidity will be maintained in the storage space i8.

It will thus be observed that by this arrangement of cooling coils or cooling means, the evaporator unit has a high efiiciency not only for icements in the boiler absorber of a single inter mittent unit. The other pair consists of cooling coils 21a and 29a connected to collecting tanks 26a and 25a, respectively, similarly supplied with refrigerant in out of phase relation to the first mentioned pair.

Each cooling coil has an inlet connection for refrigerant liquid with the bottom of the respective collecting tank and also has a return or outlet connection for refrigerant vapor with the upper portion of the collecting tank. For purposes of clarity, the return or outlet connection from each coil to the upper portion of the respective collecting tankhas been omitted.

The cooling coils 21 and 29 of. one pair of evaporating systems are arranged respectively on the right and left sides of the ice freezing compartment 2| while the cooling coils 21a and 29a of the other pair of evaporating systems are arranged respectively on the left and right sides of said compartment so that each side of the compartment 2| is provided with a cooling coil of the first-named pair and a cooling coil of the second- Each of the cooling coils 21 and 21a is in thermal contact with the ice freezing compartment 2| while each of the cooling coils 29 and 29a is out of thermal contact with said compartment so that an air channel 24 between cooling coil 29 and cooling coil 21a is provided along the left side of the ice freezing compartment 2| and a similar channel 241: between cooling coil 21 and cooling coil 29::

the right side of said compartmnt.

In this form of the invention, the vertical plates 22 and 22a are secured to the inner edges of the cooling coils 23 and 22a, respectively, and

the vertical cooling fins 23 and 23:: extend inwardly into the corresponding air channels 24 and 24a on opposite sides of the compartment 2| to cool the air circulating therethrough.

The operation of the difierent evaporating systems of the evaporator unit just described is believed obvious without further description, it being clear from the previous explanation in connection with Figs. 1 and 2 that one pair of cooling coils, for example coil 21 and 29 will operate to produce cold, while the other pair of coils 21a and 29a is beingv filled with liquid refrigerant so that during one operating period, one side of the ice-freezing compartment 2| will be cooled by one coil in thermal contact therewith, while the air on the other side of the compartment is cooled by the coil out of thermal contact with the compartment. During the alternate operating period, the air on first mentioned side of the ice-freezing compartment will be cooled by the cooling coil out of thermal contact with the compartment, while the other side of the compartment i cooled directly by the coil 21a in thermal contact therewith.

If desired, the compartment 2|, together with the cooling coils in thermal contact therewith may be surrounded by a shield or the like 28, hav. ing a suitable opening in the bottom thereof for the outlet of water condensate formed on the walls of the compartment and the cooling coils. The outer edges of the other cooling coils separate from the first named coils may also be shielded to form closed coils by any suitable means such as members 30 and 30a shown in connection with coils 29 and 29a, respectively, in Fig. 3. .Moreover, the entire evaporator unit may be shielded as shown in this figure by a metallic shell or the like suitably shaped to provide vertical side walls 3| on opposite sides of the evaporator unit, and converging bottom wall 32 and 33 across the bottom of the evaporator unit, said converging bottom wall terminating in spaced relation to I one another to define an opening below which a removable tray 34 is suitably supported to collect condensate dripping from the coils and falling onto the converging walls 32 and 33. The top of the shell is open and preferably spaced below the top of the storage space I8 "topermit the circula-- tion of air through the evaporator unit and into the storage space as indicated by the arrows.

In Fig. 4, the converging walls 32 and 33 adjacentthe bottom of the evaporator unit are shown secured to the lowerends of the vertical plates 31 and 31a welded to the cooling coils 36 and 36a respectively, of separate alternately operating evaporating systems, said converging walls terminating in suitably shaped end portions forming a support for the removable condensate collecting tray 34. \As in the previously described constructions, the plates 31 and 31a are provided with vertical ribs or fins 38 and 38a, respectively, which, in this instance. extend inwardly into the channels 24 and 24a on opposite sides of the compartment 2|. Also, separate coils 39 and 39a,

oppositely disposed with respect to the corredefrosting cooling coils. This cold moisture-laden air may be utilized to cool a low temperature compartment 4| for crisping lettuce or the like, which compartment is arranged immediately'below the ice-freezing compartment 2 From the channels 24 and 24a, the air passes into the main storage space l8 oi the cabinet through the openings 32' and 33' provided in the converging walls 32 and 3! respectively.

In Fig. 5, the evaporator unit consists of an icefreezing compartment 2 a low temperature compartment 40 disposed below the same, and a top compartment 45 placed above the ice-freezing compartment 2|. In this form of the invention, separate cooling coils 46 and 46:; from respective collecting tank 41 and 41a are thermally connected to opposite Sides of the ice-freezing compartment 2i, while separate cooling coils 48 and 48a from the respective collecting tanks 41 and 41a are disposed above the corresponding coils 45a and 46 and are arranged in spaced relation to the adjacent sides of the top compartment 45. Each of the cooling coils 46 and 48 has an inlet connection for refrigerant liquid with the bottom of the connecting tank 41! and also has a return or outlet connection for refrigerant vapor with the upper portion of said tank. Similarly, each of the cooling coils 46a and 48a has an inlet connection for refrigerant liquid with the bottom of the collecting tank 41a and also has a return or outlet connection for refrigerant vapor with the upper portion of said tank. For purposes of clarity, the inlet connection of each coil with the respective collecting tank has been omitted. The finned vertical plates 22 and 22a secured to the coils 48 and 48a, respectively, form separate air channels 49 and 49a with the adjacent side walls of the top compartment 45, and the lower portions of the vertical walls of the shield 3| arranged on opposite sides of the ice-freezing compartment 2| andthe low temperature compartment 40 form continuations of the air channels 49 and 49a.

The coils '46 and 48 operate in unison in out of phase relation to the corresponding coils 46a and 480 as indicated by the arrows showing the direction of flow of the refrigerant, so that when the second-mentioned coils are operating to produce cold, the air entering the top of the channel 49a from the storage space l8 will be cooled by coil 48a and will circulate downwardly along the adjacent sides of the compartments 45, 2| and 40, while the air entering the top of the channel 49 will not be cooled appreciably until it comes in contact with the coil 46a which is thermally connected to the ice-freezing compartment 2|. Thus with the particular arrangement of cooling coils just described, a higher temperature will be maintained in the top compartment 45 than in either of the other compartments 2| and 40, so that said top compartment may be employed to store food stuffs not requiring low storage temperatures, such for example as butter, eggs, etc.

Instead of employing separate coils from a common collecting tank, or from separate collecting tanks of one or more intermittent unitsoperating in out of phase relation to the corresponding coils of the other unit or units, single coils may be utilized, each coil having a portion in thermal contact with one side of the ice-freezing compartment 2|, and another portion oppositely disposed with respect to the first mentioned portion and spaced from the corresponding side of the compartment. In this event, the liquid rei'rigerant will be delivered first to the first mentioned portion of the corresponding coil and then to the second mentioned portion. Such an arrangement is shown in Fig. 6, where, for convenience, only one cooling coil 54 and a portion of a collecting tank 5| are illustrated forming one-half of the evaporator unit, said coil having one portion 52 in thermal contact with one side of the ice-freezing compartment 2| and a second portion 53 to which is welded the vertical plate 22 provided with cooling fins 23, said second portion 53 being arranged in spaced relation to the opposite side of the compartment 2| and above thelatter to provide an air channel similar to that previously described in connection with Fig. 5. The alternately operating evaporating system is the same as that just described but its cooling coil is oppositely disposed with respect to the first coil so that during the operation of the refrigerating apparatus, a cold air space is provided on each side of the compartment.

In Fig. 7, a slightly modified coil arrangement forming one-half of a modified form of evaporator unit is shown consisting of a cooling coil 55a having a portion 56a in thermal contact with one side of the ice-freezing compartment 28 and a second portion 51a provided with a vertical finned plate 22a arranged at substantially the same level as the first portion but on the opposite side of the compartment 2i and spaced therefrom, said second portion being connected to said first portion 56a by a sloping portion 58a of the cooling coil which extends downwardly from the upper end of the first portion across the back of the compartment 2| to the bottom of the second portion. In this manner. refrigerant from the collecting tank 5la will flow first to the first portion 56a and then to the second portion 51a and evaporate in both of said portions to produce cold.

While the invention has been described in connection with refrigerating apparatus of the intermittent absorption type, the same is equally applicable to continuous systems of refrigeration either of the absorption type or of the compressor type wherein the refrigerant circulates substantially continuously from the source of generation or compression. However, in this type of refrigcrating apparatus the flow of the refrigerant is diverted intermittently through separate evaporating systems by any suitable control means, one form of which is shown as an example in Fig. 8 comprising a closed vessel divided centrally by a vertical partition 8| to form two separate chambers 82 and 82a adapted to be supplied with refrigerant liquid through branch conduits 83 and 83a, respectively, from a condenser 84. v From the bottom of the chambers 82 and 82a the refrigerant liquid flows through cooling coils 85 and 85a, respectively, the former having a portion 85 in thermal contact with one side of the ice-freezing compartment 2|, and a second portion 81 arranged in spaced relation to the opposite side of the compartment 2| and above the latter. Cooling coil 85a is similar to coil 85 but its portions 86a and 81a areoppositely disposed with respect to thgcorresponding portions 86 and 81' and the sides of the compartment 2|. As in the previously described constructions, the portions 81 and 81a of the coils have welded thereto the vertical plates 22 and 22a provided with ribs or fins 23 and 23a to form relatively large cooling surfaces spaced from one another and from the compartment 2 The ilow of liquid refrigerant into and from the chambers 82 and 82a is controlled by a pair of double valve mechanisms generally indicated as 88 and 88a, respectively, operable intermittently in alternate relation to each other by a control lever I! fulcrumed intermediate its ends and IOIa. Each of the circuits I and I00a has as at 80 and being movable on its fulcrum by a float 8| influenced by the liquid level in one of the chambers, for example, chamber 82. Valves 82 and 02a, provided at one end of the valve mechanisms 88 and 881:, respectively, cooperate with separate valve seats to control the inlet flow of liquid refrigerant from the branch conduits 83 and 820 into the corresponding chambers 82 and 82a, while separate valves 93 and 93a are provided at the opposite ends of the valve mechanisms 88 and 88a adapted to cooperate with separate valve seats to control the outlet of liquid refrigerant from the chambers 82 and 82a to the corresponding cooling coils 85 and 85a. One end of the lever 89 is operatively connected to valve mechanism 88 by means of a lost motion connection provided by spaced abutment-forming pins 94 and 95, while the other end of the lever is similarly connected to valve mechanism 88a by means of similar pins 94a and 95a. Snap springs 98 and 96a cooperate with the valve mechanisms 88 and 88a, respectively, to yieldably maintain said mechanisms in either of their extreme oper-' ating positions.

Having described one form of control means for a heat dissipating portion I03 and I03a, respectively, arranged above the coil portions thereof and disposed in separate insulated chambers I04 and W411. Liquefied refrigerant or other suitable cooling agent is supplied intermittently and alternately to the chambers I04 and mm by way of conduits or the like I05 and IBM, respectively,

intermittently diverting the flow of refrigerant in a continuous refrigerating system through separate evaporating circuits or cold producing parts, its operation is as follows:

Assuming that the parts occupy the position shown in full lines in Fig. 8 of the drawings, liquid refrigerant will be admitted from the condenser 84 through branch conduit 83 to collect in chamber 82, while the liquid refrigerant previously collected in chamber 82a flows through the cooling coil 85a. As soon as the liquid level in chamber 82 reaches a predetermined point, lever 89 will actuate valve mechanisms 88 and 88a to open valve 93 and close valve 92 of valve mechanism 88 and simultaneously close valve 93a and open valve 82a of valve mechanism 88a. During this period the refrigerant liquid'will flow from the condenser 88 through the branch conduit 88a and into chamber 82a and collect in the latter, while the refrigerant previously collected inchamber 82 will flow through the cooling coil 88. From the respective cooling coils 85 and 85a, the refrigerant returns to the source of generation or compression to again pass through the condenser 84 and repeat the cycle of operations Just described.

Instead of forming separate portions of a circult or of separate circuitsthrough which the refrigerant circulates, the cold producing .parts of the evaporator unit heretofore described may be formed into separate closedcircuits in which a secondary refrigerant is circulated intermittently and alternately, the primary refrigerant flowing through the primary circuit or circuits, or any other suitable cooling a ent being employed to intermittently and alternately liquefy leading from a suitable source (not shown), and the cooling effect produce by such cooling agent, or. by evaporation of the refrigerant in said chambers, liquefles' the refrigerant evaporated in the coil portions of the respective circuits I00 and I 00a and passing through the corresponding heat dissipating portions I03 and I03a. Thus, the cooling agent, or the refrigerant of a primary circuit or circuits is employed to dissipate the heat from the closed circuits I00 and I00a while the latter form the actual cold producing refrigerant circuits of the evaporator unit.

From the foregoing it is believed that the construction and advantages of the improved evaporator unit forming the subject of the present application may be readily understood by those skilled in the art without further description, it being borne in mind that numerous changes may be made in the details disclosed without departing from the spirit of the invention as set out in the following claims.

What I claim is:

1. In a refrigerator having a thermally insulated storage space; the combination of a plurality of cooling sections divided into two groups and arranged to provide a cooling unit in said storage space having a plurality of channels for a circulating medium, each channel being formed between a separate pair of cooling secthe secondary refrigerant in the respective secondary circuits. I

Such an arrangement'is shown in Fig. 9 comprising a pair of closed circuits generally indicated as I00 and Illa, each having coil portions I8I, I02, and Illa, I020, respectively, forming tions, each pair comprising a cooling section of one group and a. cooling section of theother group, and means to flow refrigeration fluid to each of said groups of cooling sections intermittently but in out of phase relationship one group to the other.

2. In a refrigerator having a thermally insulated storage space; the combination of a plurality of cooling sections divided into two groups and arranged to provide a cooling unit in said storage space having a plurality of channels for circulating air, each air channel being formed between a separate pair of cooling'sections comprising a cooling section of one group and a cooling section of the other group, one of the cooling sectionsof the first group and forming one of the cooling sections associated with one of said air channels and one of the cooling sections of the second group and forming one of the cooling sections associated with another one of said air channels being arranged to form low temperature cooling means, and means to flow refrigeration fluid to each of said groups of cooling sections intermittently but in out of phase relationship one group to the other.

3. In refrigerating apparatus including .two thermally insulated receptacles supplied with a cooling fluid intermittently but in out of phase relation to one another; the combination of a cooling unit including two cooling sections associated with one of said receptacles to produce refrigeration intermittently and two other cooling sections associated with the other one of said receptacles to produce refrigeration intermittently but in out of phase relation to the first named cooling sections, said first named and second named cooling sections being arranged to rality of evaporator to provide substantially continuous refrigeration,

each unit having a plurality of cooling parts including one for ice-freezing and another for air cooling with the ice-freezing part of one unit arranged in direct thermal transfer relation to the ice-freezing part of the other unit and with the air cooling part of the first unit arranged adjacent to and in indirect thermal transfer relation to the ice-freezing part of the second unit and the air-cooling part of the second unit arranged adjacent to and in indirect thermal transfer relation to the ice-freezing part of the first unit to provide separate paths for circulating air, the air in each path of flow being cooled substantially continuously by passing in thermal exchange with an air-cooling part of one unit and an ice-freezing part of the other unit.

5. In a refrigerator having a thermally insulated storage space; the combination of a plurality of evaporator parts having alternate cooling and inactive periods and arranged in pairs in said storage space with the evaporator parts of each pair operating in out of phase relation to one another, a compartment having heat conducting walls thermally connecting one of the evaporator parts of each of said pairs and ar-' ranged to provide a low temperature zone in indirect thermal transfer relation to the other one of the evaporator parts of each of said pairs, and separate wall-forming means on said other one of the evaporator parts of each of said pairs arranged in parallel relation to the adjacent walls of said compartment to provide channels for circulating air in said storage space.

6. In a refrigerator having a thermally insulating storage space; the combination of a plurality of evaporator parts having alternate cooling andinactive periods and arranged 'in pairs in said storage space with the evaporator parts of each pair operating in out of phase relation to one another, a compartment having heat conducting walls in thermal contact with one of the evaporator parts of each of said pairs and arranged to provide a low temperature zone spaced inwardly-from the other one of the evaporator parts of each of said pairs, separate wall-forming means on said last named evaporator parts of each of said pairs arranged in parallel relation to the adjacent walls-ofsaid compartment and spaced outwardly therefrom to provide channels for circulating air in said storage space, and heat transferring fins on each of said wall-forming means.

'1. In a refrigerator having a thermally insulated storage space; the combination of a pluparts having alternate cooling and inactive periods and arranged in pairs in said storage space with the evaporator parts of each pair operating in out of phase relation to one another, a compartment having heat conducting walls in thermal contact with one of the evaporator parts of each of said pairs and arranged to provide a low temperature zone spaced inwardly from the other one of the evaporator parts of each of said pairs, separate wall-forming means on said last named evaporator parts of each of said pairs arranged in parallel relation to the adjacent walls of said compartment and spaced outwardly therefrom to provide channels for circulating air in said storage space, and heat transferring fins on each of said wall-forming means projecting inwardly into the corresponding channels.

8. In a refrigerator having a thermally insulated storage space; the combination of a plurality of evaporator'parts having alternate cooling and inactive periods and arranged in pairs in said storage space with the evaporator parts of each pair operating in out of phase relation to one another, a compartment having heat con ducting walls in thermal contact with one of the evaporator parts of each of said pairs and arranged to provide a low temperature zone spaced inwardly from the other one of the evaporator parts of each of said pairs, separate wall-forming means on said last named evaporator parts of each of said pairs arranged in parallel relation to the adjacent walls of said compartment and spaced outwardly therefrom to provide channels for circulating air in said storage space, and heat transferring fins on each of said wall-forming means projecting outwardly from the corresponding channels.

9. In a refrigerator having a thermally insulated storage space; the combination of a plurality of evaporator parts having alternate cooling and inactive periods and arranged in pairs in said storage space with the evaporator parts of each pair operating in out of phase relation to one another, a compartment having heat conducting walls thermally connecting one of the evaporator parts of each of said pairs and arranged to provide a low temperature zone in indirect thermal transfer relation to the other one of the evaporator parts of each of said pairs, separate wall-forming means on said other one of the evaporator parts of each of said pairs arranged in parallel relation to the adjacent walls of said compartment to provide channels for circulating air in said storage space, and a shield surrounding said low temperature zone.

10. In a refrigerator having a thermally insulated storage space; the combination of a plurality of evaporator parts having alternate cooling and inactive periods and arranged in a number of separate pairs in said storage space with the evaporator parts of each pair operating in out of phase relation to one another, a compartment having heat conducting walls in thermal contact with one of the evaporator parts of each of said pairs and arranged to provide a low temperature zone spaced inwardly from the other one of the evaporator parts of each of said pairs, separate wall-forming means on said last named evaporator parts of each of said pairs arranged in parallel relation to the adjacent walls of said compartment and spaced outwardly therefrom to provide channels for circulating air in said storage space, an auxiliary compartment disposed below said low temperature zone, and means forming continuations of said wall-forming means to direct the air flowing in each of said channels along the walls of said auxdiary compartment.

11. In combination with a compartment to b cooled; refrigerating apparatus including tWi thermally insulated vesselssupplied with refrigerant liquid intermittently and in out of phase relationship, a pair of cooling Darts associated with one of said vessels, and a separate pair of .with said compartment, and the other one of the cooling parts of each of said first and second pairs being arranged on another side of said com artment with the cooling part of the first pair out of thermal contact and the cooling part of the second pair in thermal contact with said compartment.

12. In combination with a compartment to be cooled; refrigerating apparatus including two thermally insulated vessels supplied with refrigerant liquid intermittently and in out of ,phase relationship, a pair of cooling part associated with one of said vessels, a separate pair of cooling- Parts associated with the other one of said Vessels, one of the cooling parts of each of said first and second pairs being arranged on one side of said compartment with the cooling part of the first pair in thermal contact and the cooling part of the second pair out of thermal contact with said compartment, and the other one of the cool-- parts of each of said first and second pairs being arranged on another side of said compart-. ment with the cooling part of the first pair out of thermal contact and the cooling part of the second pair in thermal contact with said compartment, and heat conducting means on each of vsaid cooling parts arranged out of thermal conment and another pair on another side of said compartment, one of the cooling elements of each ,of said first and second-named pairs being thermally bonded to said freezing compartment to cool the latter and the other one of the cooling elements of each of said first and second-named pairs being arranged out of thermal contact with said freezing compartment to cool the air in said storage chamber circulating in heat exchange relation with the respective sides of said freezing compartment, and means constructed and artact with said compartment for increasing the heat transferring surfaces thereof.

13. Arefrigerator comprising, in combination, a cabinet having a thermally insulated storage chamber and a freezing compartment to be cooled;

and refrigerating apparatus for cooling said chamber and compartment including a plurality of cooling elements arranged in pairs includin one pair on oneside of said freezing compartment and another pair on another side of said compartment, one of the cooling elements of each of said first and second-named pairs being thermally bonded to said freezing compartment to cool the latter and the other one of the cooling elements of each of saidfirst and second-named pairs being arranged out of thermal contact with said freezing compartment to cool the 'air in said storage chamber circulating in heat exchange relation with the respective sides of said freezing compartment, and means constructed and arranged to operate intermittently one of the cooling elements of each of said pairs as a group and the other one of the cooling elements of each of said pairsasanother group.

14. A refrigerator comprising, in combination, a cabinet having a thermally insulated storage chamber and a freezing compartment to be cooled; and refrigerating apparatus for cooling said chamber and compartment including a plurality of cooling elements arranged in pairs includin one pair on one side of said compertranged to supply refrigerant liquid intermittently to one of the cooling elements of each of said pairs for operation as a roup and to the other one of the cooling elements of each of said pairs for operation as another group.

15. A refrigerator comprising, in combination, a cabinet having a thermally insulated storage chamber and a freezing compartment to be cooledyand refrigerating apparatus for cooling said chamber and compartment comprising a pair of intermittent absorption refrigerating units 4 each including a pair of evaporator parts, one of the evaporator parts of one of said units and one of the evaporator parts of the other one of said units being arranged on one side of said freezing compartment with the evaporator part of' said first-named unit thermally bonded to said freezing com artment to cool the latter and the evaporator part of the second-named unit arranged out of thermal contact with said freezing compartment to cool the air in said storage chamber circulating in heat exchange with said side of the freezing compartment, and the other one of the evaporator parts of each of said units being arranged on another side of said freezing compartment with the evaporator part of said second- ,named unit thermally bonded to said freezing compartment to cool the latter and the evaporator part of said first-named unit arranged out of thermal contact with said freezing compartment to cool the air in said storage chamber circulatin in heat exchange relation. with the said side of said freezing compartment.

16, In combination with a compartment to be cooled; refrigerating apparatus including a plu-' rality of vessels supplied with refrigerant liquid intermittently, and a plurality of cooling elements divided into groups including one group associated with half of said vessels and another group associated with the other half of said vessels, one of the cooling elements of the first group nd one of the cooling elements of the second group beingarranged on one side of said compartment with said first-named cooling element thermally bonded to said compartment and said second-named cooling element arranged outof thermal contact with said compartment, and another one of the cooling elements of thefirst group and another one of the cooling elements of the second group being arranged on another side of said compartment 'with'said first-named cooling element out of thermal contact with said compartment and said second-named cooling element thermally bonded, to said compartment.

NILS ERLAND u- KLEEN. 

